Abbaszadeh M, et al. - Perioperative intravenous corticosteroids reduce incidence of atrial fibrillation following cardiac surgery: a randomized study
Rev Bras Cir Cardiovasc 2012;27(1):18-23
Table 3. Postoperative side effects of the Patient Groups Characteristics AF during 24 hours after cardiac surgery[%(n)] AF(72 hours after cardiac surgery) [%(n)] Mortality (n) Myocardial infarction(n) Urinary tract infection(n) Pulmonary infection(n) Wound infection(n)
Placebo (n= 92) 62.5(35) 62.7(32) 1 6 1 1 2
Dexamethasone (n= 92) 37.5(21) 37.3(19) 0 4 0 2 3
P Value 0.025* 0.032* 0.31 0.51 0.31 0.56 0.65
Numbers (n) and percentages (%). *Significant different
DISCUSSION Atrial fibrillation is the most common arrhythmia occurring after cardiac surgery. Its incidence varies depending on type of surgery. Postoperative AF may cause hemodynamic deterioration, predispose to stroke and increase mortality. Effective treatment for prophylaxis of postoperative AF is vital as it reduces hospitalization and overall morbidity [18]; however, it is believed that the systemic inflammatory response to surgery may play a role in the development of AF [19]. Levels of C-reactive protein are elevated in patients with AF, and prior work has demonstrated that corticosteroids reduce these levels in nonoperative AF [17]. Corticosteroids have anti-inflammatory activity and reduce exaggerated inflammatory reaction [20]. Halonen et al. [19] observed that the concentration of C-reactive protein was significantly lower postoperatively in the hydrocortisone group than in the placebo group. The study by Dernellis & Panaretou [17] also found that corticosteroid therapy reduces both C-reactive protein values and the risk of recurrent and permanent AF in nonoperative patients. We reported the results of the first, to our knowledge, prospective, double-blind, randomized multicenter trial investigating the effects of corticosteroid treatment on the incidence of postoperative AF after cardiac surgery. We found that intravenous dexamethasone reduced the relative risk of postoperative AF by 37.5% compared with placebo in patients undergoing CABG surgery. The effects of corticosteroid treatment on postoperative AF have been addressed earlier in 2 randomized controlled trials with postoperative AF as the primary endpoint [5,2122]. Prasongsukarn et al. [21] studied 86 patients scheduled for CABG surgery who were administered 100 mg of methylprednisolone or placebo before surgery and 4 mg of dexamethasone or placebo every 6 hours for 24 hours after surgery. Postoperative incidence of AF was significantly lower (21%) in the corticosteroid group than in the placebo group (51%). Halvorsen et al. [5] administered 4 mg of dexamethasone or placebo after induction of anesthesia and on the first postoperative morning in 300 patients
undergoing CABG surgery. The incidence of postoperative AF was lower among patients randomized to the dexamethasone group vs. the placebo group (27% vs. 32%, respectively). Whereas in our study we administered 6 mg of dexamethasone or placebo after induction of anesthesia and on the first postoperative morning. In the study by Halonen et al. [19] corticosteroid medication was continued for 72 hours. There was a relatively low incidence of postoperative AF (32%) in the placebo group in the study by Halvorsen et al. [5] compared with the study by Halonen et al. [19] (48%) and our study (37.5%). Methylprednisolone was found to have a statistically significant inhibitory effect on the incidence of AF postoperatively [22]. The study by Yared et al. [6] enrolled 235 patients for CABG. The patients were administered a single dose of 0.6 mg/kg of dexamethasone or placebo after induction of anesthesia. Compared with the placebo group, the dexamethasone group had a lower incidence of postoperative AF (19% vs. 32%). Although the results of these studies are interesting, it is difficult to compare them with our study. Previous studies have found several predictors of AF after cardiac surgery [23]. To adjust for these confounding factors, we performed a multivariable analysis in which independent predictors such as age, sex; body mass index (BMI), cross-clamp time, surgery time, extracorporeal circulation, peripheral anastomoses, and central anastomoses were taken in to account. After adjustment for these factors, corticosteroid treatment remained a significant independent predictor of the absence of postoperative AF. Increased risk of wound infections and gastrointestinal bleeding (stress ulcer) can be a concern with a corticosteroid therapy [20]. We found administration of dexamethasone therapy feasible and well tolerated, and noted no serious complications associated with intravenous administration of the drug. In the study by Prasongsukarn et al. [21], no difference was found between the corticosteroid and placebo groups in major complications, but the corticosteroid groups had minor complications. In our study, there were no more complications in the Dexamethasone group than in the placebo group. 21